With improvements and developments in science and technology, people's desire of enjoyment in material life and spiritual level has always been increased and never reduced. In the era of rapid changes in technology, people hope to realize unrestrained imagination by display device to achieve immersive experience. Therefore, how to make the display device display stereo images has become an anxious target to achieve in display technology. In one kind of the stereo display devices, a phase retarder film having two different phase regions is attached outside a display panel, to make lights provided by pixel regions for displaying left-eye images and lights provided by pixel regions for displaying right-eye images have different polarization states. By means of this, lights for the left-eye and lights for the right-eye respectively pass through polarization lenses with different polarization states of a polarization glasses, and then the left eye and the right eye of a user can receive different images, thereby establishing stereo images in user's mind.
In order to prevent the lights provided by the pixel region from diagonally passing through an improper phase retardation region and therefore delivering an improper image to the user. A black matrix is disposed between the pixel regions for the left-eye image and the pixel regions for the right-eye image, and further, an area of the black matrix is increased for enhancing a vertical viewing angle of the stereo image. However, for the high resolution display device, the increase of the area of the black matrix decreases light transmittance of the display device. A solution of this problem is to periodically input a right-eye image signal, a dark state signal, a left-eye image signal and a dark state signal in sequence to the display panel and make the area of the phase region of the phase retarder film be substantially equal to twice of the area of the pixel region. As a result, the display device could have the better light transmittance when displaying two-dimensional images and the better three-dimensional viewing angle when displaying stereo images.
However, in the forgoing display device that the area of the phase region is substantially as twice as the area of the pixel region, light and dark stripes (i.e. stripe mura) are generated in the images when the display device displays the two-dimensional images, and the stripe mura is more obvious when viewed at a greater viewing angle. The phase retarder film is a multilayer film coated by materials with different phase retardations, such that different portions of a surface of the phase retarder film have different refractive indexes, thereby generating the stripe mura in the image. Therefore, how to solve or improve the abovementioned problems has become one of the key concerns in display technology.